Common false impression – getting sufficient quantities of omega-3 from fortified foods

The media may be saturated with the message that omega-3s are good for us, but it seems that there is still a lack of knowledge over what omega-3 is, and what exactly we are consuming when we eat foods that are fortified with omega-3. In the latest omega-3 report – 2010 US Consumers’ Choice: Omega-3 Nutrient Products – dairy products and beverages fortified with omega-3 are the two categories that have seen the highest sales increase over the past two years in the omega-3 market. Other foods commonly fortified are bread and spreads. Consumers, it seems, are influenced mainly by what they see on the television and what they read on the internet.

What consumers really need to understand is that not all omega-3s are created equal, particularly when it comes to such things as heart health and brain function. In fact, it is well established that dietary omega-3 polyunsaturated fatty acids are involved in health promotion and disease prevention, but specifically and uniquely those omega-3s that are derived from fish. It is these omega-3s and these omega-3s only that are needed for proper growth and development in foetuses, infants and children, and for the regulation of immune function, inflammatory function and cardiovascular regulation at all ages.

The difficulty with adding marine derived omega-3s to everyday food items is that these long chain fatty acids are prone to rancidity when exposed to air, raising issues with both taste and the product’s shelf life. However, fortifying food items with the short chain omega-3 alpha-linolenic acid (ALA) derived from plants does not pose with the same problems, as ALA is significantly more stable than the long chain fatty acids eicosapentaenoic acid (EPA) and docosahexanoeic acid (DHA). However, whilst ALA is an omega-3 fatty acid, is does not offer the same health benefits as that of EPA or DHA, as it is simply a precursor to these longer chain fats. Indeed, consumed sources of ALA (such as flaxseeds and hemp seeds) must be physically modified before offering any significant health benefits, a process that is extremely inefficient in humans. In fact, the conversion of ALA to EPA and DHA is consistently low in most people; less than 8% of ALA is metabolised to EPA and only between 0.02% and 4% is metabolised to DHA. Although there is currently no Recommended Daily Allowance (RDA) for omega-3 fats in the UK, the government do suggest a daily intake of 450mg a day for adults and 200mg for children. However, these figures are specifically for long chain omega-3s. Consumers may still be under the false impression that they’re getting sufficient quantities of omega-3 simply by using a fortified spread or breads when the reality is that many fortified foods often contain fairly insignificant levels of omega-3, or are fortified with short chain ALA, and they would need to eat huge amounts to achieve any significant health benefits.

So if you are under the impression that you are boosting your intake of beneficial fats as you place your ‘omega-3 laced’ loaf of bread into your trolley, you may have to think again. Make sure you read the label as this will give a clear indication as to the source, and if it doesn’t state EPA or DHA then you might want to head for the fish counter. The alternative is, of course, to supplement your diet with a quality fish oil (I recommend omega 3 fish oil Vegepa) and, if you really are not a fish lover, try supplementing with echium oil; Echiomega may not be a fish oil but it’s certainly superior to other plant sources of omega-3.

Man’s best friend and more?

Last week saw a rather unusual story in the headlines in which a jack Russell took it upon itself to remove an infected toe from his sleeping owner. Jerry Douthett, a 48-year-old musician from Rockford, USA, had been out drinking, and on returning home had fallen into a deeper than usual sleep. He awoke, some hours later, to find the sheets of his bed blood soaked, and on further investigation, found the big toe that had been infected for several weeks, but for which he had not sought medical attention, had disappeared. It turned out that Kiko, the family dog, had detected the infection and chewed the toe to the point that is was completely removed. Whilst the story had a an edge of humour to it, it came to light that Mr Douthett had in fact been suffering from type II diabetes, a condition he was unaware of, but for which he is now is being treated. Some of the long term damaging effects of diabetes are to the blood vessels and nerves that supply the limbs. Neuropathy is the direct damage of nerves and results in gradual loss of sensation and, if the skin is damaged, can result in infection, as experienced first hand by Mr Douthett. Unfortunately, many people have type II diabetes for years without knowing it, simply because any early symptoms can be vague and may not cause undue concern, or seem important at the time. Symptoms, amongst others include feeling thirsty all the time, frequent urination, unexplained tiredness and unexplained weight loss, muscle wasting and frequent infections, or slow-healing sores. It is important, therefore, to be aware of these symptoms and visit your GP if you have any concerns. Catching diabetes early is a key factor to managing the condition successfully. In Mr Douthett’s case he had his dog’s ability to smell his infection to thank, as it has enabled him to now regulate his glucose levels and hopefully avoid any further losses!

A dogs’ ability to detect infection is not surprising, given their acute sense of smell, believed to be around 100,000 times more acute than that of humans. The distinct olfactory gift that is associated with the canine species has, in fact, led scientists to conduct small-scale studies of dogs’ ability to detect the chemical markers of cancer, specifically melanoma, with extremely promising results. Much of the research in this area is based on the theory that a disease causes subtle chemical changes in the body, or alterations in metabolism, which in turn releases a different smell or chemical marker to which dogs can be trained to recognise. Whilst the concept that dogs may be used as a cancer diagnostic tool is doubtful, their use in heath care is certainly of significance. Indeed, their use as guide dogs and hearing dogs is now advancing to their use to warn their owners of epileptic seizures, low blood sugar and heart attacks to name but a few. So they really are man’s best friend!

Remembering the importance of lifestyle choices

There has been a flurry of journal publication lately focusing on methods that can help stave off cognitive impairment and dementia. According to the most recent study, published in this month’s British Medical Journal, making dietary and lifestyle changes that ultimately reduce the risk of developing diabetes and depression, could have a significant impact on an individual’s future risk of developing dementia (Ritchie et al, 2010). The study, led by French researcher Dr Karen Ritchie, of the French National Institute of Medical research, analysed the lifestyle and health of 1,433 people over the age of 65 living in the south of France over a period of seven years. Whilst there is an element of genetic risk associated with the development of dementias such as Alzheimer’s disease, the role of diet and lifestyle are long known to be of significance, and that risk can be manipulated through specific changes. Dr Ritchie was quoted as saying “health chiefs should focus on encouraging literacy, prompt treatment of depressive symptoms and early screening for glucose intolerance and insulin resistance”. The study also highlighted the importance of consuming plenty of fruit and vegetables associated with a more ‘Mediterranean’ style of eating, which would also involve the consumption of foods such as seafood which is rich in neuroprotective omega-3s. In regards to the protective role that long term education has on brain health, this recent publication supports the findings of a study published in last months journal Brain. This study involved examining the brains of 872 participants in ECLIPSE (Epidemiological Clinicopathalogical Studies in Europe), a collaboration between three large population-based studies of ageing, in which a positive association was found between education and a reduced risk of developing dementia symptoms (Brayne et al, 2010). What was particularly interesting about this study was that education had no protection on dementia itself, but only on the symptoms. When the brains of individuals were examined, those individuals who had stayed in education still, showed the pathological and molecular signs of dementia, although whilst living, those individuals showed no physical symptoms of dementia. This would suggest that education in early life appears to enable some people to cope with a lot of changes in their brain before showing dementia symptoms.

So what do we learn from this? It seems that the same messages re-emerge over and over. That exercise, education and adoption of a ‘healthy’ diet offer protection against a myriad of diseases and conditions that are often considered to be just a part of growing old. However whilst it appears that we have a lot more say in our long term fate, putting into practice the advice offered by scientist may take both time and dedication as many of us are very settled in our ways. Educating people is the first step in initiating long term lifestyle changes.

Ritchie K et al. (2010) Designing prevention programmes to reduce incidence of dementia: prospective cohort study of modifiable risk factors. BMJ August 2010

Brayne C et al. (2010) Education, the brain and dementia: neuroprotection or compensation? Brain 133:2210-2216

Boil, steam or fry: are we getting the best from our vegetables?

The message that we need to consume our 5-a-day (about 800g of fruit and vegetables in total) is one that appears to be making a positive impact on people’s food choices. By eating fruits and vegetables that are of a variety of different colours, you can get the best all-around health benefits. Fruit and vegetables are termed ‘whole foods’, and are rich in a large amount of nutrients, such as vitamins, minerals, fibre and phytochemicals. Tomatoes for example are extremely rich in lycopene, a phytochemical that is suggested to reduce risk of cancer by activating special cancer preventive enzymes called phase II detoxification enzymes, which remove harmful carcinogens from cells and the body. When it comes to children, we all know how fussy they can be, and it’s often useful to offer them small amounts of different coloured types that can be less overwhelming than one large portion of dreaded broccoli.

Whilst many types of fruit and vegetable can be eaten as they are, many can’t, and many of us choose not to consume them in their raw state. But what is the effect of different cooking methods on their macronutrient and antioxidant capacity?

Microwave cooking has gained considerable importance as an energy-saving, convenient, and time-saving cooking method. However, the effects on our food remain controversial. Whilst the effects of microwave cooking on nutritive values of moisture, protein, carbohydrate, lipid, minerals, and vitamins appear minimal, it is the actual changes in the molecular structure of nutrients that still seem unclear and as a consequence many people choose to avoid or certainly limit its use.

Generally, water is not the cook’s best friend when it comes to preparing vegetables. Many of the vitamins and minerals within vegetables and fruit are water soluble, and therefore any cooking process that involves contact with water will deplete levels of nutrients to different extents (boiling is the worst, whilst steaming is much more nutrient friendly). Stir frying on the other hand, usually involves the use of some kind of culinary oil into which water soluble nutrients are unable to enter. Not only does stir frying help retain nutrient levels, but also the resulting texture and colour can be more appetising than other cooking methods (and it’s quick!).

Overall, there will always be a loss in nutritional value of foods, however, the degree of vitamin and mineral losses from food is influenced by various factors, for example the type of food, variety of food, the way of cutting, preparation, duration and method of cooking.

Why must man play God in the food chain?

There was a time when the phrase ‘cloning’ only really existed in science fiction novels and the minds of small boys. However, our ability to progress scientifically blossomed in 1996 in the form of Dolly the cloned sheep; hitting the headlines, she caused quite a stir, highlighting the endless possibilities of such a feat as well as many ethical dilemmas. Dolly was cloned from a single mammary cell (and therefore very aptly named after the singer Dolly Parton) by a process called ‘nuclear transfusion’ in which the nucleus of one cell is injected into the empty shell of another, creating a ‘new cell’ with the ability to divide like a normal developing embryo. Dolly lived for 6 years and produced 6 lambs of her own, remaining the most famous sheep in the world. Whilst cloning of animals can be viewed as a viable tool for preventing the extinction of species, and even possibly for reviving extinct species, it seems that such a procedure is being vastly misused. I awoke this morning to the news that milk from the offspring of cloned cows has made its way into UK supermarkets. As a result the Food Standards Agency, the authority responsible for accepting novel food applications, is currently investigating such claims, as the sale of milk from such cows is currently illegal under UK food regulations. It both amazes and concerns me that we don’t seem to have enough dairy cattle in the first place, and that as consumers, we have no say in such processes, and no ways of identifying such products on our shelves as, apparently, the milk in question is neither labelled nor identified in any way.

There are huge ethical concerns over the long-term health consequences that arise from such procedures as cloning, and consequences that we should really have learn from past errors in playing God in the food chain. Take transfats for example. The hydrogenation process by which trans fats are formed was first discovered around the turn of the 20th century, and so with it was born the first man-made fat to join the food supply. American kitchens were the first to introduce partially hydrogenated vegetable oil in 1911 with a product called Crisco®. The incorporation of transfats in to many food products soon became popular with consumers and food manufacturers because they acted as a preservative, giving foods a longer shelf life but also giving foods a more appealing taste and texture. The devastating effects of these fats are now abundantly clear, with links to cardiovascular disease and metabolic syndrome, and consequently we are now desperate to deplete these fats completely from our diets. So it seems we have learnt very little from past mistakes.

Cloning is one form of genetic manipulation to suit a dietary ‘need’; another is the genetic modification of plants to produce genetically modified (GM) end products. This process isolates and modifies genes, usually so that they function better, before inserting into a new species. The end result is to develop an organism that expresses a novel trait that is not normally associated with that species. GM foods first hit the market in the early 1990s and were restricted to transgenic plant products such as soybean, corn, canola, and cotton seed oil. The objections that are raised against GM foods include possible safety issues, ecological and economic concerns – all of which are still prominent and, consequently, use of GM in the food chain is still of great concern.

Another such potential use of a GM plant species is to genetically modify plants to produce essential omega-3 fatty acids that are usually only associated with fish and fish oils. The drive behind such a process is an attempt to increase omega-3 in human diets without adding pressure to fish stocks. If successful, the resulting plants are aimed at feed for farm animals, and for incorporation into the food chain through direct inclusion in food products as an indirect way of increasing our omega-3 levels. Consequently, the consumer may be completely unaware of such processes, and that GM products are even being incorporated into every day food products. Whilst GM omega-3 may not be the next trans fat, and that it is hoped that the heath positive benefits outweigh any heath negative attributes, we do not know at this point the long term heath consequences of such actions.

I would like to have the choice to make up my mind and not have to actively seek out foods that are free from GM. Would you?